Instruction - operation code (opcode)

Cpu Moore Law Transistor


An opcode (operation code) is the first part of an instruction that is read by the decoder to select the device (circuit) that implements the operations.

It's a unique number that identifies an operation.

Each opcode is a member of the instruction set.


A opcode is a digit. Assembly language gives name to opcode that are called mnemonic.


In a assembly format, simple opcode example

opcode 1100, 1100
# if opcode corresponds to the binary 00, it's the same as

Documentation / Reference

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